move-files-and-2-renames (#4285)

maths/two_sum.py

@@ -0,0 +1,47 @@
+"""
+Given an array of integers, return indices of the two numbers such that they add up to
+a specific target.
+
+You may assume that each input would have exactly one solution, and you may not use the
+same element twice.
+
+Example:
+Given nums = [2, 7, 11, 15], target = 9,
+
+Because nums[0] + nums[1] = 2 + 7 = 9,
+return [0, 1].
+"""
+from __future__ import annotations
+
+
+def two_sum(nums: list[int], target: int) -> list[int]:
+    """
+    >>> two_sum([2, 7, 11, 15], 9)
+    [0, 1]
+    >>> two_sum([15, 2, 11, 7], 13)
+    [1, 2]
+    >>> two_sum([2, 7, 11, 15], 17)
+    [0, 3]
+    >>> two_sum([7, 15, 11, 2], 18)
+    [0, 2]
+    >>> two_sum([2, 7, 11, 15], 26)
+    [2, 3]
+    >>> two_sum([2, 7, 11, 15], 8)
+    []
+    >>> two_sum([3 * i for i in range(10)], 19)
+    []
+    """
+    chk_map = {}
+    for index, val in enumerate(nums):
+        compl = target - val
+        if compl in chk_map:
+            return [chk_map[compl], index]
+        chk_map[val] = index
+    return []
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
+    print(f"{two_sum([2, 7, 11, 15], 9) = }")